Neuroblastoma

What is Neuroblastoma?

Neuroblastoma is a cancer that develops from nerve cells found in several areas of the body. Neuroblastoma most commonly affects children age 5 or younger, though it may rarely occur in older children and adults. Neuroblastoma is the most common cancer in babies.

Neuroblastoma develops in tissue that makes up the sympathetic nervous system — the system of nerves that automatically regulates your heart rate, blood pressure and digestion. Neuroblastoma most commonly arises in and around the adrenal glands, which sit atop the kidneys. However, neuroblastoma can also develop in other areas of the abdomen and in the chest, neck and pelvis.

About 650 people are diagnosed with neuroblastoma each year in the United States, according to the American Cancer Society. For those diagnosed at an early stage, the chance for a cure is good. For older children and those with advanced neuroblastoma, outcomes generally aren't good. However, research into new treatments continues and may one day improve survival rates for children with neuroblastoma.

What is the Neuroblastoma Symptoms?

Signs and symptoms of neuroblastoma vary depending on what part of the body is affected. About two-thirds of all neuroblastomas occur in the abdomen, usually in or near the adrenal glands. About 15 percent of neuroblastomas arise in the chest. Less frequently, neuroblastoma occurs in the neck or pelvis. Occasionally the site of origin of a neuroblastoma can't be determined.

Neuroblastoma in the abdomen may cause signs and symptoms such as:

• Abdominal pain
• A feeling of fullness in the abdomen
• A mass under the skin that isn't tender when touched
• Changes in bowel habits, such as constipation
• Changes in urinary habits, such as having to go to the bathroom more often
• Swelling in the legs

Neuroblastoma in the chest may cause signs and symptoms such as:

• Wheezing
• Swelling in the face
• Changes to the eyes, including drooping eyelids and unequal pupil size

Other signs and symptoms that may indicate neuroblastoma include:

• Lumps of tissue under the skin
• Eyeballs that seem to protrude from the sockets (proptosis)
• Back pain
• Curvature of the spine (scoliosis)
• Fever
• Unexplained weight loss
• Bone pain

What is the Neuroblastoma Cause?

In general, cancer begins with a genetic mutation that allows normal, healthy cells to continue growing without responding to the signals to stop, which normal cells do. Cancer cells grow and multiply out of control. The accumulating abnormal cells form a mass (tumor). Cancer cells may invade nearby tissues and can break off from an initial tumor to spread elsewhere in the body (metastasize).

Neuroblastoma begins in neuroblasts — immature nerve cells that a fetus makes as part of its development process in the womb. As the fetus matures, neuroblasts eventually turn into nerve cells and fibers and the cells that make up the adrenal glands. The majority of neuroblasts mature by birth, though studies have found a small number of immature neuroblasts in newborns. In most cases, these neuroblasts will mature or disappear. Others, however, form a tumor — a neuroblastoma.

It isn't clear what causes the initial genetic mutation that leads to neuroblastoma. However, because neuroblastoma usually affects very young children, researchers believe the mutation occurs during pregnancy, or possibly even before conception.

What is the Neuroblastoma Treatment?

Your child's doctor selects a treatment plan based on several factors that affect your child's prognosis. Factors include your child's age, the stage of the cancer, the type of cells involved in the cancer, and whether there are any abnormalities in the chromosomes and genes. Using this information, your child's doctor categorizes the cancer as low risk, intermediate risk or high risk.

What treatment your child receives for neuroblastoma depends on the risk category. Treatment may include surgery, chemotherapy, radiation, bone marrow stem cell transplant or a combination of these treatments.

Surgery
Surgeons use scalpels and other surgical tools to remove cancer cells. In children with low-risk neuroblastoma, surgery to remove the tumor may be the only treatment needed. Whether the tumor can be completely removed depends on its location and its size. Tumors that are attached to nearby vital organs — such as the lungs or the spinal cord — may be too risky to remove. In intermediate-risk and high-risk neuroblastoma, surgeons may try to remove as much of the tumor as possible. Other treatments, such as chemotherapy and radiation, may then be used to kill remaining cancer cells.

Chemotherapy
Chemotherapy uses chemicals to kill cancer cells. Chemotherapy targets rapidly growing cells in the body, including cancer cells. Unfortunately, chemotherapy also damages healthy cells that grow quickly, such as cells in the hair follicles and in the gastrointestinal system, which can cause side effects. Children with low-risk neuroblastoma that can't be removed surgically may receive low doses of chemotherapy. Sometimes chemotherapy is administered before surgery (neoadjuvant chemotherapy) to shrink the tumor to a size that's more easily removed. In other cases, chemotherapy may be the only treatment.

Children with intermediate-risk neuroblastoma often receive a combination of moderate-intensity chemotherapy drugs. Chemotherapy is often given before surgery to improve the chances that the entire tumor can be removed.

Children with high-risk neuroblastoma usually receive high doses of chemotherapy drugs to shrink the tumor and to kill any cancer cells that have spread elsewhere in the body. Chemotherapy is usually used before surgery and before bone marrow stem cell transplant.

Radiation therapy
Radiation therapy uses high doses of energy particles to destroy cancer cells. Radiation therapy primarily affects the area where it's aimed. Your child's radiation therapy team tries to protect the healthy cells near the cancer, but some healthy cells may be damaged by the radiation. What side effects your child experiences depends on where the radiation is directed.

Children with low-risk or intermediate-risk neuroblastoma may receive radiation therapy if surgery and chemotherapy haven't been helpful. Children with high-risk neuroblastoma may receive radiation therapy after chemotherapy and surgery to prevent cancer from recurring.

Stem cell transplant
Children with high-risk neuroblastoma may receive a transplant using their own blood stem cells (autologous stem cell transplant). The bone marrow makes stem cells, which mature and develop into the red and white cells and platelets that make up the blood. Your child undergoes a procedure that filters and collects stem cells from his or her blood. Then high doses of chemotherapy are used to kill any remaining cancer cells in your child's body. Your child's stem cells are then injected into his or her body, where they can form new, healthy blood cells.